The purpose of this study is to test a biobehavioral model that implicates the hemodynamic pattern of behaviorally-evoked blood pressure responses in the pathogenesis of hypertension and concentric left ventricular hypertrophy. Sympathetic nervous system function will be evaluated extensively, as it is postulated to contribute to race and gender differences in the hemodynamic patterns of blood pressure regulation to aid in determining pharmacological and/or behavioral treatment for hypertensive heart disease.